Manual machine tool

ABSTRACT

The invention is based on a power tool comprising toolholder ( 12, 102 ) driveable in at least rotary fashion via a drive motor and via a driven shaft ( 10, 98, 100 ), which comprises a workholding fixture ( 14 ) for attaching tools ( 16, 104 ) actuatable in the direction of rotation of the driven shaft ( 10, 98, 100 ), and comprising a locking device ( 18, 86, 90 ), via which the driven shaft ( 10, 98, 100 ) is coupleable in torsion-resistant fashion for locking and releasing the workholding fixture ( 14 ) to and from a housing part ( 20, 106 ), and which opens automatically when torque is transferred from the drive motor to the toolholder ( 12, 102 ), and which locks automatically when torque is transferred from the toolholder ( 12, 102 ) to the drive motor. 
     It is proposed that the locking device ( 18, 86, 90 ) is located on the driven shaft ( 10, 98, 100 ).

RELATED ART

The invention is based on a power tool comprising a toolholder driveablein at least a rotary fashion via drive motor and via a driven shaft,which comprises a workholding fixture for attaching tools actuable inthe direction of rotation of the driven shaft, and comprising a lockingdevice, via which the driven shaft is coupleable to and from a housingpart in a torsion-resistant fashion for locking and releasing theworkholding fixture, and which opens automatically when torque istransferred from the drive motor to the toolholder, and which locksautomatically when torque is transferred from the toolholder to thedrive motor.

A hammer drill having a drive motor located in a housing and outfittedwith a locking device was made known in DE 198 03 454 A1. Using thelocking device, a drilling spindle drivable by the drive motor islockable to the housing of the hammer drill in torsion-resistantfashion, so that a drill chuck screwed together with the drillingspindle can be released from the drilling spindle and/or a tool can bekeylessly clamped into the drill chuck. The locking device is located onan intermediate shaft that is coupleable to the drilling spindle via twogear steps.

The locking device opens automatically when torque is transferred fromthe drive motor to the drill chuck and locks automatically when torqueis transferred from the drill chuck to the drive motor.

ADVANTAGES OF THE INVENTION

It is proposed that the locking device is located on the driven shaft.The means of attaining the object of the invention can thereby be usedadvantageously in power tools without intermediate shaft, such as withsingle-pass drills or hammer drills, etc., in particular. Using thelocking device, tools can be keylessly clamped into and released fromthe toolholder, in particular in a toolholder designed as drill chuck.Moreover, a toolholder can be easily screwed onto the driven shaft andunscrewed from the driven shaft. The driven shaft can be designed asone- or two-pieced, or integrated with a drive shaft of the drive motor.

If one part of the locking device is formed by a toothed gear located onthe driven shaft, via which the driven shaft is driveable, thencomponents, space, installation expense, and costs can be saved inadvantageous fashion. Generally speaking, the locking device can also beformed out of additional components as well.

The locking device can be realized by means of various coupling typesappearing practical to one skilled in the art. A particularly simple,space-saving and cost-effective design having few components can beachieved using a claw clutch, however, that comprises at least one clawthat is secured in the toothed gear. The claw is preferably formed by abolt having a round cross-sectional area. Bolts of this type can beadvantageously designed as cost-effective standard components and canfurther be secured in recesses producible in cost-effective fashion,e.g., in bore holes.

In a further embodiment of the invention, it is further proposed thatthe locking device comprise a washer that comprises at least one drivingelement for transferring torque, and the washer is located on a firstseat of the roller bearing of the driven shaft in torsion-resistantfashion, and the toothed gear is located on a second seat of the rollerbearing of the driven shaft in rotatable fashion. An advantageouslyspace-saving and cost-effective design having a one-part driven shaft,in particular, can be achieved. Generally speaking, the washer can alsobe located on the driven shaft in rotatable fashion and the toothed gearcan be located on the driven shaft in torsion-resistant fashion.

Components can be further spared by fixing the driven shaft in positionin at least one axial direction via the washer, e.g., by pressing thewasher preferably onto the driven shaft and fixing it in position in atleast one axial direction via a stop that can be formed by a housingpart, for example.

The driven shaft has a cross-section deviating from a cylindrical shape,preferably in the region of the first seat of the roller bearing, toform a geometrical positive connection with the washer. The washer canthereby be connected particularly securely to the driven shaft intorsion-resistant fashion without additional components. Generallyspeaking, however, the washer can also be secured in torsion-resistantfashion to the driven shaft via other non-positive, positive, and/orbonded connections appearing practical to one skilled in the art, suchas pressing on, etc.

In a further embodiment, it is further proposed that the washer islocated on a side of the toothed gear facing the toolholder. Usingminimal design changes, existing, sophisticated designs can be utilized.In hammer drills in particular, an impact mechanism can be located instandard fashion on the side of the toothed gear opposite to thetoolholder.

To further save space, additional components, and installation expense,the driven shaft is advantageously supported in an arresting position ofthe locking device in the direction of rotation via the washer and viaat least one body in a component or in a housing part, via whichcomponent, moreover, bearing forces of the driven shaft are supported inthe maching housing. In the arresting position of the locking device,the washer is preferably supported in a washer connected intorsion-resistant fashion to a housing part or directly in the housingvia one or more rolling elements. An additional washer can becoordinated in advantageous fashion in terms of the materialspecifically with the stresses that occur. When support takes placedirectly in a housing part, additional components, space, and weight canbe saved.

The bearing forces can be supported directly in the component or theycan be supported advantageously in the component or housing part via apot-shaped component designed separate from the housing part. Theseparately-designed, pot-shaped component can advantageously be producedout of metal or a highly loadable material having a thin wall thickness,by way of which space can be saved. Moreover, the separate, pot-shapedcomponent can be adapted cost-effectively to different embodimentshaving different bearings, e.g., to embodiments having needle rollerbearings and embodiments having sliding bearings, etc.

Moreover, the means of achieving the object according to the inventionis usable especially advantageously in grinders, in angle grinders inparticular. A locking device to be operated manually can be spared, thespace can be reduced, and comfort can be increased. In angle grinder,the locking device can be located before or after an angular gear. Ifthe locking device is located before the angular gear, high speedsusually occur at the locking device, but so do low torques, so thelocking device can be designed to be space-saving and low-weight. If thelocking device if located after the angular gear, low speeds and hightorques occur at the locking device, but the angular gear can beprotected from high torques during installation and removal of a bitinsert. Depending on the design and area of application of themanually-guided angle grinder, one or the other alternative can beadvantageous.

If at least one part of the locking device, in particular a lockingring, is rigidly connected to this component by means of the manufactureof a component of the angular gear, the installation expense can bereduced. If the locking ring is injected into a component of the angulargear, advantageously into a plastic bearing flange, the lockingring—despite an overall lightweight design and a realizable, simpleinstallation—can be produced out of a hard material adapted for itsfunction, e.g., out of hardened metal. Generally speaking, the lockingring can also be designed integral with a housing part, however, or itcan be connected to this in non-positive, positive, and/or bondedfashion after its manufacture.

BRIEF DESCRIPTION OF THE DRAWING

Further advantages result from the following description of the drawing.The drawing, the description, and the claims contain numerous featuresin combination. One skilled in the art will advantageously consider themindividually as well and combine them into reasonable furthercombinations.

FIG. 1 shows a schematic representation of a hammer drill,

FIG. 2 shows an enlarged section II from FIG. 1 in a longitudinal view,

FIG. 3 shows an exploded diagram of components from FIG. 2,

FIG. 4 shows a view along the line IV-IV in FIG. 2, in an openingposition of a locking device,

FIG. 5 shows an enlarged view V in FIG. 4,

FIG. 6 shows a view along the line IV-IV in FIG. 2 in an arrestingposition of the locking device,

FIG. 7 shows an enlarged view VII in FIG. 6,

FIG. 8 shows an angle grinder from above,

FIG. 9 shows an exploded diagram of a region labelled “IX” in FIG. 8,and

FIG. 10 shows a variant of FIG. 9.

DETAILED DESCRIPTION OF THE EXEMPLARY EMBODIMENTS

FIG. 1 shows a schematically-represented hammer drill comprising a drivemotor located in a machine housing 20 and not shown further, by means ofwhich a spur-toothed wheel 22 located on a drilling spindle 10 via adrive shaft 72, and a quick-action drill chuck 12 is driveable inrotating and impacting fashion via the drilling spindle 10 (FIGS. 1, 2,and 3).

The drilling spindle 10 is supported in a needle roller bearing 54 onthe side of the spur-toothed wheel 22 opposite to the drill chuck 12,which needle roller bearing 54 is supported in the machine housing 20via a locking disc 56 of a latching impact mechanism 64 and via abearing bracket 58. The locking disc 56, with its detents, can bebrought into connection with detents 70 integrally molded to thespur-toothed wheel via a switching device (not shown) in axial direction40 against a compression spring 68. The drilling spindle 10 is supportedin a needle roller bearing 60 on the side of the spur-toothed wheel 22facing the drill chuck 12, which needle roller bearing 60 is supportedin the machine housing 20 via a pot-shaped plate part 52 and via aplastic gearbox cover 50.

The drill chuck 12 is connected to the drilling spindle via a threadedjoint 62 and comprises a workholding fixture 14 for attaching bits 16,which workholding fixture 14 is actuatable in the direction of rotationof the drilling spindle 10. Moreover, the hammer drill comprises alocking device 18 via which the drilling spindle 10 is coupleable intorsion-resistant fashion for releasing and locking the workholdingfixture 14 from and to the machine housing 20, and which opensautomatically when torque is transferred from the drive motor to thedrill chuck 12 and locks automatically when torque is transferred fromthe drill chuck 12 to the drive motor.

According to the invention, the locking device 18 designed as clawclutch is located on the drilling spindle 10. A part of the lockingdevice 18 is formed by the spur-toothed wheel 22 supported in rotatablefashion on a seat of the roller bearing on the drilling spindle 10, viawhich spur-toothed wheel 22 the drilling spindle 10 is driveable by thedrive motor. Four claws 24, 26, 28, 30—each of which has a roundcross-sectional area, are designed as bolts, and are situated parallelto the axis—are pressed into bore holes in the spur-toothed wheel 22.

The locking device 18 further comprises a washer 42 pressed onto thedrilling spindle 10 on the side of the spur-toothed wheel 22 facing thedrill chuck 12, on which washer 42 two driving elements 32, 34 extendingin the radial direction for transferring torque are integrally molded(FIGS. 2 and 4). The driving elements 32, 34 are shaped in such afashion that the washer 42 is rotatable with limitation between theadjacent claws 24, 26, 28, 30.

The washer 42 has a nearly cylindrical basic shape on its outercircumference abutting the driving elements 32, 34, which transitionsinto one flat spot 74, 76 each in the center between the adjacentdriving elements 32, 34. The washer 42 is surrounded by a locking ring48 that comprises a cylindrical basic shape having four flat spots 78,80, 82, 84, via which it is held with positive engagement intorsion-resistant fashion in the gearbox cover 50. Due to the flat spots74, 76 of the washer 42, the locking ring 48 comprises a differentradial distance from the washer 42 and, in fact, a larger radialdistance in the region of the flat spots 74, 76, and a smaller radialdistance in the region of the cylindrical basic shape. The claws 24, 26,28, 30 have a slight motional play in the region of the cylindricalbasic shape of the washer 42.

In the center region of the flat spots 74, 76 of the washer 42,cylindrical rolling elements 44, 46 are accommodated with slightmotional play between the washer 42 and the locking ring 48, thediameter of which is greater than a diameter of the claws 24, 26, 28,30.

The washer 42 is pressed onto a seat of the roller bearing 36 of thedrilling spindle 10, and the drilling spindle 10 has a cross-sectiondeviating from a cylindrical shape in the region of the seat of theroller bearing 36 of the washer 42 to form a geometrical positiveconnection in the direction of rotation with the washer 42 (FIG. 4). Thedrilling spindle 10 is fixed in position in an axial direction 40 viathe washer 42 and, in fact, in the direction 40 of the drill chuck 12via a stop formed by the gearbox cover 50. The gearbox cover 50 issituated rigidly in the machine housing 20.

If the drive motor drives the spur-toothed wheel via the drive shaft 72,the torque is transferred from the spur-toothed wheel 22 via the claws24, 26, 28, 30 to the washer 42, and from the washer 42 via the drillingspindle 10 to the drill chuck 12. While the claws 26, 30 grip thedriving elements 32, 34 and the torque is transferred to the washer 42,the claws 24, 28 are located in front of the rolling elements 44, 46 inthe direction of rotation and hold them in the center region of the flatspots 74, 76, in/which the rolling elements 44, 46 have a minimalmotional play toward the washer 42 and the locking ring 48 (FIGS. 4 and5). A jamming of the rolling elements 44,46 is prevented, and thelocking device 18 is opened.

If, when the drive motor is switched off, a torque is transferred fromthe drill chuck 12 via the drilling spindle 10 to the washer 42, thedriving elements 32, 34 serve to transfer torque to the claws 26, 30(FIG. 6). Due to their inertia, the rolling elements 44, 46 are forcedinto a boundary region of the flat spots 74, 76 and become stuck betweenthe locking ring 48 and the washer 42 (FIGS. 6 and 7). The drillingspindle 10 is supported in torsion-resistant fashion in the gearboxcover 50 via the washer 42, the rolling elements 44, 46, and via thelocking ring 48. The drilling spindle 10 is automatically locked inplace rigidly in the housing. Bits 16 can be clamped and released in thedrill chuck 12, and/or the drill chuck 12 can be screwed onto thedrilling spindle 10 or screwed off of the drilling spindle 10 withoutreaction torque having to be applied by hand.

The locking device 18 is designed symmetrically, so that a torque can betransferred from the drive motor in both directions via the lockingdevice 18 to the drilling spindle 10 and the drill chuck 12. The lockingdevice 18 opens automatically in both directions. Moreover, when thedrive motor is switched off, the locking device 18 locks in bothdirections of rotation when a torque is transferred from the drill chuck12 to the washer 42 via the drilling spindle 10.

FIG. 8 shows an angle grinder from above having an electric motor (notshown) supported in a housing 112. The angle grinder is guideable via afirst handle 114 extending in the longitudinal direction and integratedin the housing 112 on the side opposite to an abrasive cutoff wheel 104,and via a second handle 116 extending transverse to the longitudinaldirection and attached to a gearbox housing 106 in the region of theabrasive cutoff wheel 104.

FIG. 9 shows an exploded drawing of a region of the angle grinderlabelled “IX” in FIG. 8 having a locking device 86. In the exemplaryembodiments presented, components that are essentially identical arebasically labelled with the same reference numerals. Moreover, thedescription of the exemplary embodiment in FIGS. 1 through 7 can bereferred to with regard for features and functions that remain the same.

The locking device 86 is located on a driven shaft 98 of the electricmotor of the angle grinder and, in fact, in the power flux of theelectric motor in front of an angular gear 88 of the angle grinder.Starting at a fan wheel 118, a snapring 120 is located on the drivenshaft 98 of the electric motor for axial fixation, followed by a shim122 to form an axial supporting surface, a felt ring 124 havinglubricant, a ball bearing 126 for supporting the driven shaft 98, arubber ring 128 for the dampened support of the ball bearing 126, and adriven pulley 142 having four claws 144, 146, 148, 150, which, in theassembled state, is connected to the driven shaft 98 intorsion-resistant fashion via a seat of the roller bearing 36. A washer42 having two driving elements 32, 34 and two cylindrical rollingelements 44, 46 are located in a plane of the claws 144, 146, 148, 150.The washer 42 is surrounded radially outward by a locking ring 130supported in the gearbox housing 106 in torsion-resistant fashion, andis connected to a splined shaft 132 of a pinion 108 in torsion-resistantfashion via internal toothing 152. The pinion 108 is supported in thelocking ring 130 in rotatable fashion via a sliding bearing 154.

Simple assembly can be achieved by means of the connection via theinternal toothing 152 and the splined shaft 132. Generally speaking, thepinion could also be rigidly connected to the washer, however. Theangular gear 88 is driven on a grinding spindle via the pinion 108 via aring gear (not shown).

The locking device 86 basically has the same operating principle as thelocking device 18. A drive torque of the electric motor is transferredfrom the driven shaft 98, via the driven pulley 142, the claws 144, 146,148, 150, the driving elements 32, 34 of the washer 42 to the pinion108, and from the pinion 108 to the grinding spindle via the ring gear(not shown). A torque from the grinding spindle in the direction of theelectric motor, on the other hand, is supported via the ring gear, viathe pinion 108, via the washer 42, the rolling elements 44, 46, and viathe locking ring 130 in the gearbox housing 106. The grinding spindle islocked for installation and removal of the abrasive cutoff wheel 104.

FIG. 10 shows an alternative to the exemplary embodiment in FIG. 9having a locking device 90. The locking device 90 is located on a drivenshaft 100 of an angular gear 92 or on a grinding spindle. Starting at aring gear 110 of the angular gear 92, a driven pulley 156 is located onthe driven shaft 100 in the direction of a toolholder 102 integrallymolded to the driven shaft 100, which driven pulley 156 is connected intorsion-resistant fashion to the ring gear 110. Four claws 158, 160,162, 164 extending in the direction of the toolholder 102 are integrallymolded on the driven pulley 156. A washer 42 having two driving elements32, 34 and two cylindrical rolling elements 44, 46 are located in aplane of the claws 158, 160, 162, 164. A locking ring 94 of the lockingdevice 90 is injected into a plastic bearing flange 96 of the angulargear 92 in torsion-resistant fashion, which plastic bearing flange 96 isfixable in position to a gearbox housing 106 of the angular gear 92 viafour fastening screws 138. Moreover, a pressed-on ball bearing 166, afelt ring 134 having lubricant, and a dust cap 136 are located on thedriven shaft 100.

The locking device 90 has the same operating principle as the lockingdevice 18, and the washer 42 is located on a seat of the roller bearing36 on the driven shaft 100 in torsion-resistant fashion, and the ringgear 110 is located on a seat of the roller bearing 36 on the drivenshaft 100 in rotatable fashion. A drive torque of the electric motor istransferred via a pinion 140, the ring gear 110, via the driven pulley156, the claws 158, 160, 162, 164, and via the driving elements 32, 34of the washer 42 to the driven shaft 100. A torque from the driven shaft100 in the direction of the electric motor is supported at the gearboxhousing 106 via the washer 42, the rolling elements 44, 46, via thelocking ring 94, via the bearing flange 96, and via the fastening screws158.

In contrast to the locking device 86 in the exemplary embodiment in FIG.9, the locking device 90 is located in the power flux of the electricmotor after the angular gear 92 of the angle grinder.

Reference Numerals 10 Driven shaft 56 Locking disc 12 Toolholder 58Bearing bracket 14 Workholding fixture 60 Needle roller bearing 16 Tool62 Threaded joint 18 Locking device 64 Latching impact mechanism 20Machine housing 66 Detents 22 Toothed gear 68 Compression spring 24 Claw70 Detents 26 Claw 72 Drive shaft 28 Claw 74 Flat spot 30 Claw 76 Flatspot 32 Driving element 78 Flat spot 34 Driving element 80 Flat spot 36Seat of the roller bearing 82 Flat spot 38 Seat of the roller bearing 84FIat spot 40 Direction 86 Locking device 42 Washer 88 Angular gear 44Body 90 Locking device 46 Body 92 Angular gear 48 Body 94 Locking ring50 Component 96 Bearing flange 52 Component 98 Driven shaft 54 Needleroller bearing 100 Driven shaft 102 Toolholder 148 Claw 104 Tool 150Claw 106 Housing part 152 Internal toothing 108 Toothed gear 154 Slidingbearing 110 Toothed gear 156 Driven pulley 112 Housing 158 Claw 114Handle 160 Claw 116 Handle 162 Claw 118 Fan wheel 164 Claw 120 Snapring166 Ball bearing 122 Shim 124 Felt ring 126 Ball bearing 128 Rubber ring130 Locking ring 132 Splined shaft 134 Felt ring 136 Dust cap 138Fastening screw 140 Pinion 142 Driven pulley 144 Claw 146 Claw

1. A power tool comprising a toolholder (12,102) driveable in at leastrotary fashion via a driven shaft (10, 98, 100), which comprises aworkholding fixture (14) for attaching tools (16, 104) actuatable in thedirection of rotation of the driven shaft (10, 98, 100), and comprisinga locking device (18, 86, 90), via which the driven shaft (10, 98, 100)is coupleable to and from a housing part (20, 106) in torsion-resistantfashion for locking and releasing the working fixture (14), and whichopens automatically when torque is transferred from the drive motor tothe toolholder (12, 102) and locks automatically when torque istransferred from the toolholder to the drive motor, wherein the lockingdevice (18, 86, 90) is located on the driven shaft (10, 98, 100),wherein the locking device (18, 90) comprises a washer (42) thatcomprises at least one driving element (32, 34) for transferring torque,wherein the washer (42) is located on a first bearing seat (36) of thedriven shaft (10, 100) in torsion-resistant fashion, and the toothedgear (22, 110) is located on a second bearing seat (38) of the drivenshaft (10, 100) in rotatable fashion.
 2. The power tool according toclaim 1, wherein one part of the locking device (18, 86, 90) is formedby a toothed gear (22, 108, 110) located on the driven shaft (10,98,100).
 3. The power tool according to claim 2, wherein the lockingdevice (18, 90) is developed as claw clutch that comprises at least oneclaw (24, 26, 28, 30) that is secured in the toothed gear (22, 110). 4.The power tool according to claim 3, wherein the claw (24, 28, 28 30) isformed by a bolt having a round cross-sectional area.
 5. The power toolaccording to claim 1, wherein the driven shaft (10) is fixed in positionin at least one axial direction (40) via the washer (42).
 6. The powertool according to claim 1, wherein the driven shaft (10, 100) has across-section deviating from a cylindrical shape in the region of thefirst seat of the roller bearing (36) to form a geometrical positiveconnection with the washer (42).
 7. The power tool according to claim 1,wherein the washer (42) is located on a side of the toothed gear (22)facing the toolholder (12).
 8. The power tool according to claim 1,wherein in an arresting position of the looking device (18), the drivenshaft (10) is supported in a component (50) in the direction of rotationvia the washer (42) and via it least one body (44, 46, 48), via whichcomponent (50), moreover, bearing forces of the driven shaft (10) aresupported in the housing part (20).
 9. The power tool according to claim8, wherein the bearing forces in the component (50) are supported via apot-shaped component (52) designed separately from the component (50).10. The power tool according to claim 1, wherein the locking device (86)is located in the power flux of the drive motor in front of an angulargear (88).
 11. The power tool according to claim 10, wherein at leastone part (94) of the locking device (90) is rigidly connected to acomponent (96) by means of the manufacture of this component (96) of theangular gear (92).
 12. The power tool according to claim 1, wherein thelocking device (90) is located in the power flux of the drive motorafter an angular gear (88).
 13. The power tool according to claim 12,wherein the locking ring (94) of the locking device (90) is injectedinto a bearing flange (96) of the angular gear.
 14. A power toolcomprising a toolholder (12, 102) driveable in at least rotary fashionvia a drive motor and via a driven shaft (10, 98, 100), which comprisesa workholding fixture (14) for attaching tools (16, 104) actuatable inthe direction of rotation of the driven shaft (10, 98, 100), andcomprising a locking device (18, 86, 90), via which the driven shaft(10, 98, 100) is coupleable to and from a housing part (20, 106) intorsion-resistant fashion for locking and releasing the workholdingfixture (14), and which opens automatically when torque is transferredfrom the drive motor to the toolholder (12, 102), and which locksautomatically when torque is transferred from the toolholder (12, 102)to the drive-motor, wherein the locking device (18, 86, 90) comprises awasher (42) with at least one driving element (32, 34) for transmittingtorque to at least one claw (24, 26, 28, 30, 142, 144, 146, 148, 158,160, 162, 164) of one of a driven pulley (142, 156) or a toothed gear(22), wherein the driving elements (32, 34) are shaped in such a way tobe rotatable with limitation between adjacent claws (24, 26, 28, 30,142, 144, 146, 148, 158, 160, 162, 164), wherein the washer (42) has anearly cylindrical basic shape on its outer circumference abutting thedrive elements (32, 34), which transitions into a flat spot (74, 76)each in the center between the adjacent driving elements (32, 34),wherein the washer (42) is surrounded by a locking ring (48, 86, 94),and wherein in the regions of the flat spots (74, 76) of the washer (42)cylindrical rolling elements (42, 46) are accommodated between thewasher (42) and the locking ring (48, 86, 94).
 15. A power toolcomprising a toolholder (12, 102) driveable in at least rotary fashionvia drive motor and via a driven shaft (10, 98, 100), which comprises aworkholding fixture (14) for attaching tools (16, 104) actuatable in thedirection of rotation of the driven shaft (10, 98, 100), and comprisinga locking device (18, 86, 90), via which the driven shaft (10, 98, 100)is coupleable to and from a housing part (20, 106) in torsion-resistantfashion for locking and releasing the workholding fixture (14), andwhich opens automatically when torque is transferred fro the drive motorto the toolholder (12, 102), and which locks automatically when torqueis transferred from the toolholder (12, 102) to the drive-motor, whereinthe locking device (18, 86,90) is located on the driven shaft (10, 98,100), wherein the locking device (18, 36, 90) comprises a washer (42)with at least one driving element (32, 34) for transmitting torque to atleast one claw (24, 26, 28, 30, 142, 144, 146, 148, 158, 160, 162, 164)of one of a driven pulley (142, 156) or a toothed gear (22), wherein thedriving element (32, 34) is shaped in such a way to be rotatable withlimitation between adjacent claws (24, 26, 28, 30, 142, 144, 146, 148,158, 160, 162,164) wherein the washer (42) is located on a first bearingseat (36) of the driving shaft (10, 100) in torsion-resistant fashion,and the toothed gear (22, 110) is located on a second bearing seat (38)of the driven shaft (10, 100) in a rotatable fashion, wherein the washer(42) is surrounded by a locking ring (48, 86, 94 and wherein in theregion of flat spots (74, 76) of the washer (42) cylindrical rollingelements (44, 46) are accommodated between the washer (42) and thelocking ring (48, 86, 94).
 16. A power tool comprising a toolholder (12,102) driveable in at least rotary fashion via a drive motor and via adriven shaft (10, 98, 100), which comprises a workholding fixture (14)for attaching tools (16, 104) actuatable in the direction of rotating ofthe driven shaft (10, 98, 100), and comprising a locking device (18, 86,90), via which the driven shaft (10, 98, 100) is coupleable to and froma housing part (20, 106) in torsionresistant fashion for locking andreleasing the workholding fixture (14) and which opens automaticallywhen torque is transferred from the drive motor to the toolholder (12,102), and which locks automatically when torque is transferred from thetoolholder (12, 102) to the drive-motor, wherein the locking device (18,86, 90) is located on the driven shaft (10, 98, 100), wherein one partof the locking device (18, 86, 90) is formed by a tooted gear (22, 108,110) located in the driven shaft (10, 98, 100), wherein the lockingdevice (18, 90) is developed as claw clutch that comprises at least oneclaw (24, 26, 28, 30) that is secured in the toothed gear (22, 110), andwherein the claw (24, 26, 28, 30 is formed by a bolt having a roundcross sectional area.
 17. A power tool comprising a toolholder (12, 102)driveable in at least rotary fashion via a drive motor and via a drivenshaft (10, 98, 100), which comprises a workholding fixture (14) forattaching tools (16, 104) actuatable in the direction of rotating of thedriven shaft (10, 98, 100), and comprising a locking device (18, 86,90), via which the driven shaft (10, 98, 1000 is coupleable to and fromhousing part (20, 106) in torsionresistant fashion for locking andreleasing the workholding fixture (14), and which opens automaticallywhen torque is transferred from the drive motor to the toolholder (12,102), and which locks automatically when torque is transferred from thetoolholder (12, 102) to the drive-motor, wherein the locking device (18,86, 90) is located on the driven shaft, (10, 98, 100), wherein thelocking device (18, 90) comprises a washer (42) that comprises at leastone driving element (32, 34) for transferring torque, wherein the washer(42) is located on a first bearing seat (36) of the driven shaft (10,100) in torsion-resistant fashion, and a toothed gear (22, 110) islocated on a second bearing seat (38) of the driven shaft (10,100), inrotatable fashion, wherein, in an arresting position of the lockingdevice (18), the driven shaft (10) is supported in a component (50) inthe direction of rotating via the washer (42) and via at least one body(44, 48, 48), via which component (50), moreover, bearing forces of thedriven shaft (10) are supported in the housing part (20).
 18. A powertool comprising a toolholder (12, 102) driveable in at least rotaryfashion via a drive motor and via a driven shaft (10, 98, 100), whichcomprises a workholding fixture (14) for attaching tools (16, 104)actuatable in the direction of rotation of the driven shaft (10, 98,100), and comprising a locking device (18, 86, 90), via which the drivenshaft (10, 98, 100) is coupleable to and from a housing part (20, 106)in torsion resistant fashion for locking and releasing the workholdingfixture (14), and which opens automatically when torque is transferredfrom the drive motor to the toolholder (12, 102), and which locksautomatically when torque is transferred from the toolholder (12, 102),to the drive-motor, wherein the locking device (18, 90) comprising awasher (42) that comprises at least one driving element (32, 34) fortransferring torque, wherein the washer (42) is located on a firstbearing seat (36) of the driven shaft (10, 100) in torsion-resistantfashion, and the toothed gear (22, 110) is located on a second bearingseat (38) of the driven shaft (10, 100 in rotatable fashion, wherein, inan arresting position of the locking device (18), the driven shaft (10)is supported in a component (50) in the direction of rotation via thewasher (42) and via at least one body (44, 46, 48), via which component(50), moreover, bearing forces of the driven shaft (10) are supported inthe housing part (20), and wherein the bearing forces in the component(50) are supported via a pot-shaped component (52) designed separatelyfrom the component (50).
 19. A power tool comprising a toolholder (12,102) driveable in at least rotary fashion via a drive motor and via adriven shaft (10, 98, 100), which comprises a workholding fixture (14)for attaching tools (16, 104) actuatable in the direction of rotation ofthe driven shaft, (10, 98, 100), and comprising a locking device (18,86, 90), via which the driven shaft (10, 98, 100) is coupleable to andfrom a housing part (20, 106) in torsionresistant fashion for lockingand releasing the workholding fixture (14), and which opensautomatically when torque is transferred from the drive motor to thetoolholder (12, 102), and which locks automatically when torque istransferred from the toolholder (12, 102)) to the drive-motor, whereinthe locking device (18, 86, 90) is located on the driven shaft (10, 98,100), and wherein the locking device (86) is located in the power fluxof the drive motor in front of an angular gear (88).
 20. A power toolcomprising a toolholder (12, 102) driveable in at least rotary fashionvia a drive motor and via a driven shaft (10, 98, 100), which comprisesa workholding fixture (14) for attaching tools (16, 104) actuatable inthe direction of rotating of the driven shaft (10, 98, 100), andcomprising a locking device (18, 86, 90), via which the driven shaft(10, 98, 100) is coupleable to and from a housing part (20, 106) intorsionresistant fashion for locking and releasing the workholdingfixture (14), and which opens automatically when torque is transferredfrom the drive motor to the toolholder (12, 102), and which locksautomatically when torque is transferred from the toolholder (12, 102)to the drive-motor, wherein the locking device (18, 86, 90) is locatedon the driven shaft (10, 98, 100), and wherein the looking device (90)is located in the power of the drive motor after an angular gear (88).21. A power tool comprising a toolholder (12, 102) driveable in at leastrotary fashion via a drive motor and via a driven shaft (10, 98, 100),which comprises a workholding fixture (14) for attaching tools (16, 104)actuatable in the direction of rotation of the driven shaft (10, 98,100) and comprising a locking device (18, 86, 90), via which the drivenshaft (10, 98, 100) is coupleable to and from a housing part (20, 106)in torsionresistant fashion for locking and releasing the workholdingfixture (14), and which opens automatically when torque is transferredfrom the drive motor to the toolholder (12, 102), and which locksautomatically when torque is transferred from the toolholder (12, 102)to the drive motor, wherein the locking device (18, 88, 90) is locatedon the driven shaft (10, 98, 100), and wherein at least one part (94) ofthe locking device (90) is rigidly connected to a component (96) bymeans of the manufature of this component of an angular gear (92).
 22. Apower tool comprising a toolholder (12, 102) driveable in at leastrotary fashion via a drive motor and via a driven shaft (10, 98, 100),which comprises a workholding fixture (14) for attaching tools (16, 104)actuatable in the direction of rotation of the driven shaft (10, 98,100) and comprising a locking device (18, 86, 90), via which the drivenshaft (10, 98, 100) is coupleable to and from a housing part (20, 106)in torsionresistant fashion for locking and releasing the workholdingfixture (14), and which opens automatically when torque is transferredfrom the drive motor to the toolholder (12, 102), and which locksautomatically when torque is transferred from the toolholder (12, 102)to the drive motor, wherein the locking device (18, 86, 90) is locatedon the driven shaft (10, 98, 100), and wherein a locking ring (94) ofthe locking device (90) is injected into a bearing flange (96) of anangular gear.
 23. A power tool, comprising a toolholder (12, 102)driveable in at least rotary fashion via a drive motor and via a drivenshaft (10, 98, 100), which comprises a workholding fixture (14) forattaching tools (16, 104) actuatable in the direction of rotation of thedriven shaft (10, 98, 100), and comprising a locking device (18, 86,90), via which the driven shaft (10, 98, 100) is coupleable to and froma housing part (20, 106) in torsion-resistant fashion for locking andreleasing the workholding fixture (14), and which opens automaticallywhen torque is transferred from the drive motor to the toolholder (12,102), and which locks automatically when torque is transferred from thetoolholder (12, 102) to the drive-motor, wherein the locking device (18,86, 90) is locked on the driven shaft (10, 98, 100), wherein the lockingdevice (18, 90) is developed as claw clutch that comprises a pullingelement (22, 142, 156) with at least one claw (24, 26, 28, 30), saidlocking device (18, 86, 90) comprising a washer (42) located on abearing seat (36) of the driven shaft (10, 98, 100) in torsion-resistantfashion, said driven shaft (10, 100) having a cross-section deviatingfrom a cylindrical shape in the region of hearing seat (36) of thedriven shaft (10, 98, 100) to form a geometrical positive connectionwith the washer (42), said washer (42) comprising at least one drivingelement (32, 34) for transmitting torque to said claw, the drivingelement having a rounded surface for engagement with said claw, whereinthe driving element (32, 34) is shaped in such a way to be rotatablewith limitation between adjacent claws, wherein the washer (42) havingregions of flat spots (74, 76), in which cylindrical rolling elements(44, 46) are accommodated between the washer (42) and a locking ring(48, 86, 94), said locking ring (48, 86, 94) surrounding said washer,wherein, in an arresting position of the locking device (18), the drivenshaft (10) is supported in a component (50) in the direction of rotationvia the washer (42) and via at least one body (44, 46, 48), via whichcomponent (50), moreover, bearing forces of the driven shaft (10) aresupported in the housing part (20).
 24. A power tool, comprising a toolholder (12, 102) driveable in at least rotary fashion via a drive motorand via a driven shaft (10, 98, 100), which comprises a workholdingfixture (14) for attaching tools (16, 104) actuatable in the directionof rotation of the driven shaft (10, 98, 100), and comprising a lockingdevice (18, 88, 90), via which the driven shaft (10, 98, 100) iscoupleable to and from a housing part (20, 108) in torsion-resistantfashion for locking and releasing the workholding fixture (14), andwhich opens automatically when torque is transferred from the drivemotor to the toolholder (12, 102), and which locks automatically whentorque is transferred from the toolholder (12, 102) to the drive-motor,wherein the locking device (18, 86, 90) is located on said driven shaft(10, 98, 100), wherein one part of the locking device (18, 86, 90) isformed by a toothed gear (22, 108, 110) rotatable relative to the drivenshaft (10, 98, 100), the toothed gear comprising at least one claw (24,26, 28, 30) secured in the toothed gear (22, 110), wherein the lockingdevice (18, 86, 90) comprises a washer (42) with at least one drivingelement (32, 34) for transmitting torque to a toothed gear (22), saidwasher (42) being located on a bearing seat (36) of the driven shaft(10, 100) in torsion-resistant fashion, said driven shaft (10, 100)having a cross-section deviating from a cylindrical shape in the regionof said bearing seat (36) of the driven shaft (10, 98, 100) to form ageometrical positive connection with the washer (42), said washer (42)having regions of flat spots (74, 76), wherein in the regions of theflat spots (74, 76) of the washer (42) cylindrical rolling elements (44,46) are accommodated between the washer (42) and a locking ring (48, 86,94), said locking ring (48, 86, 94) surrounding the washer, wherein, inan arresting position of the locking device (18), the driven shaft (10)is supported in a component (50) in the direction of rotation via thewasher (42) and via said cylindrical rolling elements (44, 46) via whichcomponent (50), moreover, bearing forces of the driven shaft (10) aresupported in the housing part (20).
 25. A power tool comprising atoolholder (12, 102) driveable in at least rotary fashion via a drivenshaft (10, 98, 100), which comprises a workholding fixture (14) forattaching tools (16, 104) actuatable in the direction of rotation of thedriven shaft (10, 98, 100), and comprising a locking device (18, 86,90), via which the driven shaft (10, 98, 100) is coupleable to and froma housing part (20, 106) in torsion-resistant fashion for locking andreleasing the working fixture (14), and which opens automatically whentorque is transferred from the drive motor to the toolholder (12, 102)and locks automatically when torque is transferred from the toolholderto the drive motor, wherein the locking device (18, 86, 90) is locatedon the driven shaft (10, 98, 100), wherein the locking device (18, 86,90) comprises a locking ring (48, 86, 94) surrounding the driven shaft(10, 98, 100) and a washer (42), said washer (42) being located on abearing seat (36) of the driven shaft (10, 98, 100) in torsion-resistantfashion, said driven shaft (10, 98, 100) having a cross-sectiondeviating from a cylindrical shape in the region of said bearing seat(36) of the driven shaft (10, 98, 100) to form a geometrical positiveconnection with the washer (42), wherein upon torque is transferred fromthe tool holder (12, 102) to the drive motor rolling elements (44, 46)of the locking device (18, 86, 90) are automatically radially crampedbetween the washer (42) d the locking ring (48, 86, 94) fornon-rotatably coupling the driven shaft (10, 98, 100) to the housingpart, wherein upon torque is transferred from the drive motor to thetool holder (12, 102) said rolling elements (44, 46) are automaticallyreleased for allowing a rotation of the driven shaft (10, 98, 100)relative to the housing part.